First Efficient Syntheses of 1-, 4-, and 5-Caffeoylquinic Acid

✍ Scribed by Michael Sefkow; Alexandra Kelling; Uwe Schilde

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 387 KB
• Volume: 2001
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/1099-0690(200107)2001:14<2735::aid-ejoc2735>3.0.co;2-i

✦ Synopsis

Efficient synthesis of 1-, 4-, and 5-caffeoylquinic acid was achieved in three or four steps with suitably protected quinic acid precursors, in overall yields of 41%, 36%, and 60% [from quinic acid (1)]. 1-Caffeoylquinic acid was prepared by esterification of acetone quinide 7 with caffeoyl chloride 6, followed by a two-step hydrolysis of all protecting groups. Caffeoylquinic acids 4 and 5 were prepared from known quinic acid derivatives, 13 and 25, by selective esterification of the secondary hydroxy groups and hydrolysis with 1 M HCl. However, initial attempts to prepare fully protected quinic [a]